Relay

ABSTRACT

The present invention relates to an improved relay and more particularly relates to a miniaturized relay that is ideally adapted for use with present day printed circuit boards. The disclosed relay is a unit (hermetically sealed, if so desired) that snaps into place at a desired location of a printed circuit board; the terminals of the relay also serving as mechanical holding devices. Electrically, the disclosed relay may operate in several different switch modes, with a variety of input/output terminals and has the inherent characteristic that if a dual pole switching mode is used, the poles tend to operate more simultaneously than in prior art relays. Mechanically, the relay has a novel terminal construction that is efficient from both a manufacturing and an assembly point of view. Moreover, the disclosed relay is extremely economical to build.

United States'Pa tent 1 1 I 1 1111" 3,811,102

Ash v 1451 May 14, 1974 RELAY Primary Examiner-Harold Broome [75] Inventor: Leonard P. Ash, Anaheim, Calif. Atmmey 8 or & Prater [73] Assignee: Babcock Electronics Corporation,

Costa Mesa, Calif. [57] ABSTRACT [22] Filed July 22 1971 The present invention relates to an improved relay 7 and more particularly relates to a miniaturized relay 1 PP NO-I' 165,253 that is ideally adapted for use with present day printed I circuit boards. The disclosed relay is a unit (hermeti-, 52 'u.s.c1.; 335/106 335/133 335/151 cal'y Sealed, if desired) that Snaps Placeat a I I 335/202 desired location of a printed circuit board; the termi- 51 Im. c1. H0lh 50/16 relay also Serving as mechanical hlding [58] Field of Search 335/106, 107, 131,133,

Electrically, the disclosed relay may operate in several different switch modes, with a variety of input/output 335/202, 196;"317/l0lCC; 174/685 [56] References Cited terminals and has the inherent characteristic that if a UNITED STATES PATENTS I dual pole switching mode is used, the poles tend to 3 579 58 5/197] km 1 335/151 operate more simultaneously than in prior art relays.

3,171,918 3/1955 Killionm. 3,141,939 7/1964 Mink 335/202 Mechanically, the relay has a novel terminal 5/202 construction that is efficient from both a 3,246,096 4/1966 JiiCOPSOl'l 335/133 manufacturing and an assembly point of view 3,553,729 1/1971 Mori et a1. 335/106 Moreover the disclosed relay i extremely economical to build.

v 7 Claims, 6 Drawing Figures :JATENTEDHAY 14 1974 r sum 2 or 2 INVENTOR. lEONAED I? 4.5%

' l rrae/vsrs' RELAY BACKGROUND As is known to those skilled inthe field of electricity, there is a great-need for devices that will complete or will interrupt an electrical circuit and as a result of this need, many such devices have been produced a class of such devices being known under the general name of switches.

A particular type of switch has to be operated remotely and one such remotely operated switch is known as a relay. Relays are valuable for a wide variety of conditions, functions, current carrying capabilities, voltage ratings, life times, operating requirements, etc.

As the field of electricity-and especially the field of electronics-advances, there is a constantly increasing need for ever small, ever lighter weight, and even more compact relays; especially for use in the so-called printed circuit boards that are becoming so widely accepted in the'field of electronics. a It should be noted that relays which are destined for use with these printed circuit boards are usually designed for minute electrical currents, and for low voltages. Therefore, therequirements for these relays become quite differentJthan for-prior art relays.For ex ample, insulation and heating effects are no longer'a seriousproblem; but, on the otherhand, ease of installation compactness, lightweight, and reliability become ever'more important.

OBJECTS AND DRAWINGS It is therefore the principal object of the present invention to provide an improved relay.

It is another object of .the present invention to provide an improved'electrical relay that is particularly adapted for'use with present day printed circuit boards.

his still another object of the present invention to provide an improved electrical relay that may operate in a-wide variety of switching modes.

It is a further object of the present invention to provide an improved electrical relay that is smaller, lighter in weight, and more compact than prior art relays.

It is a still further object of the present invention to provide an improved method of making the terminals and elements of the relay.

The attainment of these objects and others will be realized from a study of the following detailed description taken in conjunction with the drawings of which;

FIG. I shows a pictorial view of the disclosed'relay and its method of use;

, FIG. 2 shows a top view of the working elements of the relay;

FIG. 3 shows a pictorial sectional view of a portion of the working elements;

FIG. 4,shows an exploded view of the various parts of the relay;

FIG. 5 shows a view of the relay elements in a planar configuration; and v FIG. 6 shows a pictorial view of the relay elements in their multi-planar configuration.

' SYNOPSIS Broadly speaking, the disclosed relay is a miniaturized unit that may be about 0.7 inches long, 0.3 inches high and 0.2 inches wide; its internal structure'permitting it to act as a double-pole double-throw switch. In

the finished relay, the various terminals are electrically separate from each other but the assembly process permits these terminals to be part of economical stamping that is then dropped into place in the relay housing.

Only then are the terminals electrically and mechanically separated from each other. I

The result is a small, light weight, compact, miniaturized relay that is particularly adapted for use. with the small currents and low voltages used in present day printed circuit boards.

DESCRIPTION The Basic Relay e It was pointed out above that present day miniaturizedprinted wire crcuitry requires even smaller, lighter weight, and more compact relays; and FIG. 1 shows a pictorial view of the disclosed relay connected to such tend from the interior of relay 10. The outer portions of relay elements 15, 16, 17, etc. act as interconnections or "leads; and, if desired, these lead ends may be narrowed down as indicated, in order to fit into apertures 19 of a printed-circuit board 20. the printed circuit board 20 having pads" 21 (usually annulli of electrically conducted material such as copper) that are connected, or are integral with, conductive strips 22 that form the electrically conductive printed wire pattern that gives the name to the printed circuit board. Solder 23 is used to assure good electrical and mechanical connectins between pads 21 and the relay element 15, 16, 17, etc. In this way, the inner-portions of relay 10 are electrically connected to the circuit on the printed circuit board.

Thus, electrical input signals may be applied to relay l0; and electrical output signals 'may be obtained from the various terminals of relay 10 the types of output electrical signals depending upon the particular state of the relay, whichmay be energized or de-energized remotely and electrically as conditions require. ElectricalConsiderations The electrical characteristics of the disclosed relay will be understood from a studyof FIG. 2, which is a top view of the relay looking into the relay from a level corresponding to the junction of the relay cover 10 and the relay base 12 asindicated in FIG. I.

Referring now to FIG. 2, it will be seen that relay base 12 comprise a roughly open box configuration,

having walls 25, that enclose a plurality of the above.

discussed relay elementsythese relay elements now being identified with lower case letters for a reason that will become apparent later i.e., 15a, 15b, 16a, 16b,- 17a, 17b, etc. these relay elements protruding both" inwardly and outwardly of the relay base side walls 3 straight in FIG. 2,' and projects straight through the wall 25 of relay base 12. g I

' These relay elements will all be discussedand illustrated later in much greater detail; but it may be visualized from FIGS. 1 and 2 that'straight element a comprises an outer lead end that is to be connected to the previously mentioned printed circuit board so that the outer lead end extends in a generally downward direction. Str aight element 15a also comprises a transition portion that provides a transition from the downwardly extending lead end across the top of side wall of the relay base 12', the transitionportion of the straight element extending in a generally horizontal direction. The straight element 15a also comprises an interior portion that terminates in a contact surface 27 that may be the end of the horizontal transistion pornal is appliedvto contact surface 27 of straight element 15a, the electrical signal will'be available'at the outer lead end or output terminals, that is electrically connected to the printed circuit board 20. The'Switching Element I Attention is again directed to FIG. 2, this time to one of the lower relayelements 16b; this relay element is to be calledthe switching element because (in a manner to be discussed soon) a portion of relay element 16b acts as a switch.

It may visualized from FIGS. 1 and 2, that the switching element 16b comprises an outer lead end that is to be connected to the previously mentioned printed circuit board 20; so that the outer lead extends in a generally downward direction. Switching element 16b also comprises a transistion portion that provides a transistion from the downwardly extending lead end across the top of side wall 25 of the relay base 12; this transistion portion of the switching element 16b extending in a generally horizontal direction within the relay base 12. The switching element 16b also comprises an interior portion that terminates in a switch arm b.

The configuration of the switching element 16b resembles a capital L" lying on its side, and having its short arm bent into an horizontal plane see 16b of FIG. 4; this switching element configuration being designated as a bent L" that will be furtherdiscussed later. Suffice it to say, the now horizontal portion of the bent L configuration forms-the transistion portion of the switching element 16b, while the base of the bent L configuration forms the switch arm 30b.

Because of this construction, which will also be discussed more fully later, switching element 16b of FIG. 2 has a switch arm 30b that acts as though its proximal end were pivoted" at switching element 16b, while its distal outer end moves as indicated by double ended along its switch arm 30b to the contact surface 27 of the straight element 15a. In this way, an input electrical signal applied to the input terminal switching element 4 16b may be made available at the output terminal lead endof straight element 15a.

As will be explained later, switch arm 30b maybe pivoted slightly counterclockwise, as indicated by the double ended arrow 31; so that the distal end of the switch arm 30b no longer contacts the contact surface 27. At that time, the input electrical signal applied at switching element 16b will'no longer be available at the output terminal lead-end of straight element 15a.

The above switching arrangement has been presented in terms of a single switch arm 30b and one output terminal relay element 15a; this switching arrangement being technically known as a single-pole singlethrow": S.P.S.T. switch, because a single pole (switch arm 30b) may be set (thrown) to or from a single position.

As will be discussed later, switching element 16b and its switch arm 30b areformed in such a manner that its inherent resiliency and its bias due to the forming processes cause the switch arm 30b to normally be with the contact surface 27 of straight element 15a. The technical designation for this electrical state is that the circuit is normally comp1ete;. i.e., the switch at straight element 15a'is normally closed; and the straight element 1.5a is'thus a normally closed terminal of a switching arrangement. I The Offset Element Attention is now directed, in FIG. 2, to the lower leftmost relay element 18b; this being called anoffset relay element, since it has a configuration that is offset relative to the configuration of the straight element 15a discussed previously. The reason for the offset will be discussed later.

As may be visualized from FIGS. 1 and 2, the offset element 18b comprises an outer lead end that is to be connected to the above mentioned printed circuit "board 20; so that the outer lead end extends in a generally downward direction. Offset element 18b also comprises a transistion portion that provides a transistion from the downwardly extending portion of the offset element 18b extending in a generally horizontal direction. The offset element 18b also comprises an interior offsetting elbow that terminates in a contact surface 34 that may be the horizontal end of the elbow, but is preferably a contacting surface that extends in a generally downward direction. The Switching Operation It will be noted that, for the relay illustrated in FIG. 2,.the switch arm 30b does not normally contact the contact surface 34.0f the offset element 18b. Therefore, an input electrical signal applied to the input terminal of switching element 16b would not be transferred to contact surface 34; and would not be present at the output terminal lead end of offset element 18b.

The technical designation for this electrical state is that the circuit is normally incomplete, or open; i.e.,

' the switch at the offset element 18b is normally open;

and the offset element 18b is thus a normally open terminal of the switching arrangement.

By means to be discussed later, switch arm 3011 may be moved appreciably counterclockwise indicated by the double ended arrow 31; so that the distal end of switch arm 30b no longer contacts the contact surface 27, but rather contacts the contact surface 34. At that time, an input electrical signal applied to the input terminal switch element 16b would be applied to the contactsurface 34 of the offset element 18b; and will therefore be present at the output terminal lead end of the offset element 18b.

In this way, the relay may be used to switch an input signal that is present at switching element 16b to either the straight element 15a or the offset element 18b; and in a manner to be discussed later, either condition of the'relay may be held for any desired length of time.

The above explanation has been presented in terms of a single switch arm 30b and two output terminal elements 15a and 18b; this switching mode being technically known as a single-pole double-throw S.P.D.T. switch because a single pole.(switch arm 30b) may be set (thrown) to either -of two positions.

Referring back to FIG. 2, it will be seen that the relay base 12 actually contains two sets of relay elements 15a, 16, 17a, 18a; and 15b, 16b, 17b, and 1812. These two sets of relay elements are illustrated as being identical, but as being reversed longitudinally with respect I to each other; and as being each other.

For example, 15a and 15b are both straight elements; 16a and 16b are both switching elements; and 18a and 18b are both offset elements (realy elements 17a and 1712 will be discussed later). Therefore, the above discussed switching operations may be performed by each of the two corresponding, but individual, switching arrangements (16b, 15a, 18b; 16a, 15b, 18a). in this way, the disclosed relay may operate as two single-pole double-throw relay switching arrangements; or may operate as a double-pole double-throw switching arrangement each switching arrangement handling its own individual electrical signal.

F l6. 2 illustrates that the contact surfaces, such as 27 and 34, are con vexly curved; but this curvature is not essential. The main requirement is that all contact surfaces must provide good electrical conductivity; this in opposition,.i.e., facing result being most readily obtained by suitably plating the contact surfaces gold or silver plating being preferable in order to provide long lived contact surfaces.

- It has been preferable, as a matter of convenience, to

plate the entire relay'element; as will be discussed later.

It will be noted that in FIG. 1, the external lead ends of relay elements l5, l6, l7, and 18 are illustrated as being flared slightly outwardly; this flaring aiding in snapping the relay '10 into place on the printed circuit board, and also aiding in the holding of the relay in place prior to the soldering operation that affixes the relay mechanically to the printed circuit board. Relay Operation It has thus far been explained how the disclosed relay may act as a switch of a desired type, by selecting a suitable number of relay elements, and by suitably positioning these relay elements. As indicated above, it is one of the desirable functions of a relay to be operated remotely, as by an electrical signal; and an explanation of how the disclosed relay achieves this remote control function will be understood from a further study of FIG. 2.

it will berecalled from the previous discussion that a switching arrangement such as relay 10 of FIG. 2 has one or more normally closed contacts and one or more normally open contacts. For the state of the relay illus trated in FIG. 2, the normally closed contacts are the straight elements a and 15b; and the normally open contacts are the offset elements 18a and 18b so that input signals applied to switching elements 16a and 16b would normally appear at the normally closed straight elements 15a'and 15b. This result is obtained by the curving and the biassing of the switch arms 30a and 30b so that they normally contact the straight elements 15a and 15b,- but other normal states can be achieved by other curvature and biassing of the switch arms.

A slight digression becomes desirable at this time, in

order to more fully understand the effects of magnetism. It has become customary to think that when a magnetic source is energized, magneticflux? flows out of one end of the magnetic source, flows through a magnetic circuit or loop, and then flows back into the other end of the magnetic source. In actuality, there is no actual flow; but this flowing flux concept permits a visualization of magnetic effects and it will be used in the following explanation.

It is a characteristic of magnetic flux that it needs a completely closed path, or completely closed loop,'in order to be most effective; and the loop should preferably have a low magnetic reluctance to obtain maxi-.

plished magnetically as follows. When energized, a

magnetic source, (to be discussed later) causes magnetic flux to flowout of the magnetic source; and through two pole pieces 40 and 41 of FIG. 2, as indicated by the arrows. These pole pieces 40 and 41 now serve as locations that produce localized magnetic fields.

lt will be realized at this time, that the main reason for offsetting the offset elements 18a and 18b is to provide a location for the magnetic pole pieces 41 and 42, so that the .pole pieces are located close to the distal ends of the switch arms'30a end 30b. This extreme end location of the magnetic pole pieces providesoptimal movement of the switch arms 30a and 30b.

Returning again to FIG. 2, it will be recalled that the magnetic flux flows through themagnetic pole pieces 40 and 41, through the adjacent air gaps, to the distal ends of the switch arms 30a and 30b; the air gaps forming a relatively high reluctance in the magnetic loop. In accordance with the above discussion about magnetism, the magnetic flux acts in'such a manner as to reduce the overall reluctance of the loop; and, in the present case, it reduces the reluctance by attracting the movable distal ends of the switch arms 30a and 30b closer to the fixedly positioned magnetic pole pieces 40 tion for the switch arms disappears; and the inherent resiliency and bias of the switch arms cause them to return to their normal illustrated state where they are and cobalt-vanadium-iron being typical of such special alloys. The switch arms 30a and 30b are therefore preferably made of a material of this type; and, as indicated above, are also preferably plated with gold or silver or clad" with suitable layers to enhance their electrical characteristics at the area where they contact the contact surfaces. New alloys such as nyborium give premise of possessing mechanical, magnetic, and eleccladding. The Magnetic Yoke The above discussion has treated the two switching arrangement as though they were separate from each other;.but they are actually interconnected for a very specific reason.

It will be advantageous at this time to followthe path of the magnetic flux; that is,-to trace out the magnetic loop. Starting, for convenience, at pole piece 40, the magnetic flux would flow in the direction of the arrow to the switch arm 305; would flow along switch arm 30b to the switching element l6b, would then flow along a magnetic yoke 42 to the other switching element 16a; and would then flow along switch arms30a to magnetic pole piece 41. It quickly becomes apparent that magnetic yoke 42 is a vital part of the series connected magnetic circuit, and should also be comprised of amagnetic material.

However, a close study of the electrical circuit of FIG. 2 shows the magnetic yoke 42 is also electrically connected directly across switching elements 16a and 16b; and may provide an undesired electrical interconnection, or a short. Therefore, the magnetic yoke 42 must be, per se, either an electrical insulator or must be electrically insulated from one or both of the switching elements 16a and 16b.

It has been found preferably to use the latter aptrical properties that permit their use without plating or 'proach; that is, to electrically insulate the magnetic yoke 42 from one or both of the switching elements. This result is most readily achieved by forming the magnetic yoke 42 of a magnetic material; but providing an electrically insulating film between the magnetic yoke 42 and the location where it is attached to the switching elements 16a and/or 16b. This electrically insulating film may take any of several forms. For example, it may be an air gap; alternatively it may comprise have the above discussed electrically insulating film on their inner surfaces (or on all surfaces); and the film coated inner surfaces are adhered, clamped or otherwise afiixed to the vertical surface of respective switching elements 16a and 16b. In this way, the magnetic yoke 42 completes the magnetic loop; but electrically separates the switching elements 16a and 16b.

The Simultaneous Switching It will be recalled from the above described magnetic loop,that the two switching arms 30a and 3011 are in a series type magnetic relationship; that is, the same magnetic flux flows through both switching elements 16a and 16b. This series relationship solves the following problem.

Obviously, no two switch arms have exactly the same amount of resiliency; no two magnetic pole pieces have exactly the same size and shape; no two pole piece/- switching arms will have exactly the same spacing; etc. Therefore, there is a slight tendency for the two switch arms to move at somewhat different rates; and to open or close their respective electric circuits at slightly different times. In some electronic circuits this maltiming is a serious disadvantage, because the electronics designer desires certain circuits to function similtaneously; and if these circuits do not do so because of the performance of a switching device. such as a relay, the apparatus may malfunction or the designer must design in-a safeguard.

The disclosed relay provides practically simultaneous switching, as may be understood from the following considerations. Assume that one of the switch arms, say 30b for example, tends to move faster; and to thus complete its circuit somewhat earlier than the other switch arm 30a. As the distal end of switch arm 30b approaches its respective contact surface 34, the decreased length of its air gap increases the amount of magnetic flux, and this increased magnetic flux acts on the other magnetic pole piece 41 to provide a stronger magnetic field that accelerates the movement of its associated switch arm 30a. In this way, the disclosed series type magnetic arrangement tend to equalize the movement of the two switch arms; and to provide simultaneous opening and closing of their respective circuits.

Mechanical Considerations In FIG. 4, a typical relay, made in accordance with the teachings of theresent invention, is illustrated in an I exploded manner in order to show the interrelationship a thin sheet of electrically insulating material such as an adhesive, a plastic, or the like; or it may be an electrically insulating film, such as an oxide or the like, formed chemically on one or both surfaces of the adjacent materials that form the yoke/switching element interface.

Basically, magnetic yoke 42 takes the form of a U- shaped piece of magnetic material, wherein the upright portions have been slid longitudinally away from each other, while still remaining parallel. As indicated in FIG..3, the upright portions 43 of the magnetic yoke 42 between the various mechanical parts. In FIG. 4, the relay cover 11 is shown to be a box-like configuration having walls 46; the relay cover 11 being adapted to receive an electrical coil 47 that is enclosed in a relatively tough coating 48.

The Coil Coil 47 is of the type that comprises a winding of electric wire; the wire winding of coil 47 terminating at a coil tab 49. Another such tab is on the other side of the coil 47, and thus-is not visible in FIG. 4.

When electricity flows through coil tabs 49, and thus through the wires forming the coil 47, coil 47 becomes an electro-magnet, and magnetic flux appears at end pieces such as 50 and 51 which have the previously discussed magnetic pole pieces 40 and 41 positioned at their lower ends. The pole pieces 40 and 41 now activate the switch arms 30a and 30b as discussed previously in connection with FIG. 2. Coil 47 preferably fits closely into the interior of relay cover 11'; being held 9 there by friction, suitable clamps, adhesives, or the like, the end pieces 50 and 51 projecting downwardly out of relay cover 11 as indicated.

'In'FIG. 4, the relay elements previously discussed in connection with FIG. 2 are now shown in a pictorial manner. In FIG. 4, there is shown the previously discussed straight elements 15a and 15b, the offset ele ments 18a and 18b, and the bent L switch arms 16a and 16b.

It should be noted that in FIG. 4 the contact surfaces are illustrated as being fiat rather than as being convex, and are further illustrated as having their outer lower ends extending vertically downward rather than flaring outwardly the reasons for these will become apparent from a subsequent discussion; The Coil Elements FIG. 4 illustrates two relay elements 17a and 17b that have not been previously discussed, although they were shown in the top view of FIG. 2. Relay elements 17a and 17b serve the function of contacting the coil tabs 49 illustrated as being positioned on coil 47 of FIG. 4. Relay elements 17a and 17b will therefore be called the 'coil elements; and these coil.elements 17a and 17b and the coil tabs 49 are suitable positioned to contact each other when the relay is assembled as will be discussed later.

Relay base 12 of FIG. 4 is illustrated as being box like in form, having walls'25 and a bottom 52. Preferably, the walls 25 of the relay base 12 have a plurality of notches 53 that receive the previously discussed transitional portions of the various relay elementslS, 16, 17, etc.; notches 53 actingto hold the relay elements in position during and after relay assembly, and until the relay is soldered in place on a printed circuit board.

In FIG. 4, the various relay elements 15, l6 17, etc. are illustrated as having interior portions that are downwardly directedtthese in some cases (15 and 18) acting as a contact surface, and in some cases (16) act ing as part of the switching element. In the relay element configuration of FIG. 4, these downwardly directed element portions 'serve an additional purpose; namely, that of additionally holding the relay elements in place.

As indicated in FIG. 4, relay base 12 has a support structure that may take the form of a plurality of individual prism like support pillars 54 that support the horizontal transition portions of the relay elements where they enter notches 53 of the relay base 12, these support pillars 54 serving an additional function by permitting the downwardly directed portions of the relay elements to be hooked over the vertical edges of the support pillars 54 to further support and position the relay elements within the relay base.

The vertical portions of the support pillars also support the vertical contact surfaces of the relay elements 15 and 18; and thus help provide proper pressure for making good electrical contact with the switch arms. In the case of theswitchingelements 16, the vertical portions of the support posts 54 provide a support for the bending to which the switching elements 16 are sub-' jected.

As an alternative form of the support structure, FIG. 4 also discloses a continuous support wall 55 that serves the same function asthe individual support pillaws; but may, undersome conditions, be easier to provide, especially if the relay base 12 is formed by a plastic molding process.

- The Relay Element Array- One simple way of forming the various relay elements is shown in FIGS. 5 and 6. Directing attention first to FIG. 5, this shows a planar element array 60 produced as a result of a stamping or punching operation per.-

.formed on a sheet of plated material such as the nickel ferrite mentioned above. As a result of the stamping operation, the resultant element array 60 comprises individual strips of material identified in FIG. 5 by the references characters 15a, 16a, 17a, and 180; these individual strips being interconnected by a common carrier strip 61. As may be realized, the individual strips of FIG. 5 will eventually form the various relay'ele- .ments of FIGS. 1, 2, 3 and 4.

Directing attention now to FIG. 6, the relay element array 60 is shown to have been configured by suitable bending to a multi-planeconfiguration as indicated. In FIG. 6, the carrier strip 61 has been bent horizontally to strengthen the array and has had a recntagular bend 62 formedin it to provide the desired spacing of the relay elements l6a and' 17b.

This latter item may be best appreciated by referring back to FIG. 2, which shows that the switch arms a and 30b need an appreciablelength in order to function properly in' that particular configuration. Unfortunately, the desired length for the switch arm is not conveniently available in a planar stamping configuration. Therefore, the distance between adjacent relay elements 16a and 17a is intentionally lengthened to provide the desired length for the resultant switch arm 30a.

The rectangular bend 62 of FIG. 6 provides means for later obtaining the desired spacing between these relay elements. 5 Relay Assembly The assembly of the disclosed relay is extremely simple and easy and therefore, economical as may be understood from FIG. 4. Two identical relay elements arrays (as shown in FIG. 6) are positioned in reversed opposition to each other and a magnetic yoke, 42 (shown in 'a somewhat different configuration) is then positioned as indicated in FIG. 4. The resiliency of yoke 42 v and the carrierstrips (61 of FIG. 6) act to rigidify and integralize the composite dual element arrays for easier handling. The composite dual element arrays are then dropped into respective notchesof the relay base 12 and are then hooked to respective portions of the support structure. I

The next step is the insertion of the coil 47 into the relay cover 11, and the cover/coil subassembly is then placed" atop the base/element subassembly. At this time, the coil elements 17a and 17b make contact with the coil tabs 49; the other relay elements being insulated-from the coil wire by the coating 48. Alternatively, the coil elements 17a and 17b may be bent up wardly to contact suitably positioned coil tabs 49.

The magnetic endpieces 50 and 51 of the coil 47 fit intotheir design locations;'their magnetic pole pieces 40 and 41 comingto rest at or near the bottom of the relay base 12.

The matingedges of the cover 11 and the base 12 may be held to each other with suitable adhesives,

clamps, or the like; and, if desired, the relay elements may also be held in place by means of a suitable adhesive. If such an adhesive is used, it may be of the sealing type that produces a hermetically sealed relay. The carrier strips 61 are now cut away to form 'a truncated" element array wherein the separated relay elements 1 1 can perform their mechanical, electrical, and magnetic functions.

An alternative method of assembly is to first place the magnetic yoke 42 (having the above described electrically insulating film thereon) in position on the bottom 52 of. the relay base 12 adjacent the support structure locations that will support the vertical part of the switching elements 16a and 16b. Two element arrays 60 are then positioned in opposition to each other, in the relay base 12'; the carrier strips 62 making the element arrays 60 easy to handle. In this way, the yoke, the switching element, and the support structure assure proper spacing and fit. The cover/coil subassembly is added as discussed above and the carrier strips 61 are cut away to form a truncated relay element assembly, the relay elements now being securely held in place by the notches and/or the adhesive.

It will be noted that the disclosed relay uses two identical, but reversed, element arrays to provide a doublepole double-throw switch mode. Obviously, different tyeps of element arrays may be used to achieve the same, or different switching arrangements.

Alternatively, a plurality of relay element arrays may be linked by a suitably configurated carrier strip; thus reducing the number of parts to be handled during the assembly of the relay.

The foregoing general description and exemplary body dimensions are typical of a configuration known in the integrated circuit terminology as a DIP (Dual In- Line Package); and while the circuit elements have been disclosed as being installed directlyinto a printed circuit board, these may alternatively be fitted into a socket that is, in turn, installed directly into a printed circuit board. The later arrangement provides facilities for easily replacing the relay, when this is desirable.

The installation and soldering of the elements of the relay or the socket may be accomplished manuallyor mechanically.

SUMMARY The disclosed relay has many advantages over prior art relays. First of all, it is much smaller, lighter weight and more compact. Second, it is easy to manufacture and assemble. Third, it is economical to build. Fourth, it is adapted to a wide variety of switching modes. Fifth, it produces more simultaneous opening and closing of the switch contacts. Sixth, its terminals are formed into a very convenient configuration by means of simple stamping operations. Seventh, the terminals are in a rigidized and integralized condition during assembly. Eighth, the terminals of the assembled unit are easily separated from each other. And finally, the disclosed relay is ideally adapted for use with present day printed circuit boards.

What is claimed is:'

l. A relay comprising in combination, a relay housing, an electrical winding within said housing energizable to provide magnetic flux and de-energizable to terminate said flux, means including a pair of magnetic pole pieces providing a path for the magnetic flux of said winding, a pair of movable contactors within said housing each having a stationary contact for circuit making and circuit breaking cooperation therewith, and means arranging said contactors in series relation in the path of said magnetic flux.

2. A relay according to claim 1 wherein said series arranging means comprises a magnetic flux conducting yoke magnetically interconnecting said contactors but preventing electrical energy flow therebetween.

3. A relayaccording to claim 2 wherein said yoke is so positioned relative to one of said contactors as to provide an air gap therebetween for preventing electrical energy flow while permitting magnetic flux flow in said contactors.

4. A relay according to claim 3 wherein each of said contactors and its respective stationary contact can be connected in an electrical circuit which is separate and distinct from the circuit of the other contactor and stationary contact therefor.

5. A relay according to claim 4 wherein each of said contactors includes a stationary terminal portion on which the respective contactor is mounted for arcuate movement toward and away from a separate one of said contactors is formed integrally with its terminal portion. 

1. A relay comprising in combination, a relay housing, an electrical winding within said housing energizable to provide magnetic flux and de-energizable to terminate said flux, means including a pair of magnetic pole pieces providing a path for the magnetic flux of said winding, a pair of movable contactors within said housing each having a stationary contact for circuit making and circuit breaking cooperation therewith, and means arranging said contactors in series relation in the path of said magnetic flux.
 2. A relay according to claim 1 wherein said series arranging means comprises a magnetic flux conducting yoke magnetically interconnecting said contactors but preventing electrical energy flow therebetween.
 3. A relay according to claim 2 wherein said yoke is so positioned relative to one of said contactors as to provide an air gap therebetween for preventing electrical energy flow while permitting magnetic flux flow in said contactors.
 4. A relay according to claim 3 wherein each of said contactors and its respective stationary contact can be connected in an electrIcal circuit which is separate and distinct from the circuit of the other contactor and stationary contact therefor.
 5. A relay according to claim 4 wherein each of said contactors includes a stationary terminal portion on which the respective contactor is mounted for arcuate movement toward and away from a separate one of said pole pieces in response to energization and de-energization of said winding.
 6. A relay according to claim 5 wherein said yoke is mounted in spaced relation to at least one of said terminals to provide the air gap between said contactors.
 7. A relay according to claim 5 wherein each of said contactors is formed integrally with its terminal portion. 